DETAILED ACTION
Status of Claims
Claims 1-20 are amended.
Claims 1-20 are pending.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over Hodges (US 10578709) in view of Gulati (US 20210096234).
Regarding Claim 1, 8, 15, Hodges teaches the following limitations:
A radar system comprising: one or more processors; and (Hodges – [Abstract] Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for detecting electronic counter measure (ECM) signals and embedding covert messages in radar or sonar signals. In one aspect, a method for detecting ECM signals includes receiving a radar return signal from an object. The method includes determining whether radar return signal includes a TM signal, and identifying the radar return signal as a skin return signal or an electronic counter measure signal based on whether the radar return signal includes the TM signal.)
a non-transitory computer-readable medium having stored thereon program instructions that, when executed by the one or more processors, cause the radar system to perform a set of operations comprising: (Hodges – [Abstract])
(Claim 8) A method comprising: (Hodges – [Abstract])
generating an initial radar signal comprising a plurality of rising and falling edges; (Hodges – [col. 8 ln. 54-58] A radar signal 208 in which a TM signal is embedded can include, but is not limited to, a continuous wave (CW) radar signal (e.g., the CW signal may serve as the carrier for the TM signal), a pulsed radar signal, or a modulated radar signal (e.g., a pulse compression signal such as a chirp signal).
inserting a watermark into the initial radar signal by applying one or more time shifts of one or more predetermined durations to the first subset and refraining from applying any time shift to the second subset, thereby producing a watermarked radar signal; (Hodges – [col. 3 ln. 21-34] As used herein the terms “Transpositional Modulation,” “TM modulation,” “TM,” and “TM signal” refer to techniques of adding information to a carrier signal without affecting the amplitude, frequency or phase of the carrier signal (or a signal that is modulated according to such a technique) as observed by a traditional receiver or demodulator (e.g., a non-TM capable receiver/demodulator). Transpositional modulation can be generated by several techniques. For example, in a “wide-band TM modulation” technique information is conveyed by modulating the inflection points of a carrier wave to represent data. For example, in a “harmonic TM modulation” technique information is conveyed by altering (e.g., transposing, time shifting) a harmonic of a carrier signal. Hodges does not explicitly teach “first and second subset”.)
transmitting the watermarked radar signal; (Hodges – [col. 8 ln. 54-58])
identifying a received radar signal; (Hodges – [Abstract])
determining whether the received radar signal includes one or more time-shifted rising or falling edges corresponding to the inserted watermark; (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
based on the determination of whether the received radar signal includes the one or more time-shifted rising or falling edges corresponding to the inserted watermark, determining whether the received radar signal is a skin return signal or an electronic countermeasure signal; and (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
outputting an indication of whether the received radar signal is a skin return signal or an electronic countermeasure signal. (Hodges – [Abstract])
Hodges does not explicitly teach the following limitations, however Gulati, in the same field of endeavor, teaches:
identifying (i) a first subset of one or more rising or falling edges from among the plurality of rising and falling edges and (ii) a second subset of one or more rising or falling edges from among the plurality of rising and falling edges; (Gulati – [0103] The receiving radar can determine the random phase difference between the receiving radar and the transmitting (interfering) radar using the observed phase of the subset of chirps carrying reference symbols (e.g., the “Subset 1” chirps). The receiving radar can equalize the determined phase difference for the Subset 1 chirps using the determined random phase difference. The receiving radar can then determine the Doppler and the phase code on the subset of chirps carrying the information data bits (e.g., the “Subset 2” chirps) and decode and determine the information data bits (e.g., the vehicle ID). Where the information bits indicate the ID of the transmitting vehicle, the receiving vehicle can communicate with the other vehicle (i.e., the transmitting/interfering vehicle) using the determined vehicle ID.)
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified the signal modulation of Hodges with the chirp subsets of Gulati in order to determine the random phase difference between the receiving radar and the transmitting (interfering) radar (Gulati – [0103]).
Regarding Claims 2, 9, 16, Hodges further teaches:
wherein: determining whether the received radar signal includes one or more time-shifted rising or falling edges corresponding to the inserted watermark comprises determining that the received radar signal does not include one or more time-shifted rising or falling edges corresponding to the inserted watermark; (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
determining whether the received radar signal is a skin return signal or an electronic countermeasure signal comprises determining that the received radar signal is an electronic countermeasure signal based on the determination that the received radar signal does not include one or more time-shifted rising or falling edges corresponding to the inserted watermark; and (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
outputting the indication of whether the received radar signal is a skin return signal or an electronic countermeasure signal comprises outputting an indication that the received radar signal is an electronic countermeasure signal. (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
Regarding Claims 3, 10, 17, Hodges further teaches:
wherein: determining whether the received radar signal includes one or more time-shifted rising or falling edges corresponding to the inserted watermark comprises determining that the received radar signal does include one or more time-shifted rising or falling edges corresponding to the inserted watermark; (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
determining whether the received radar signal is a skin return signal or an electronic countermeasure signal comprises determining that the received radar signal is a skin return signal based on the determination that the received radar signal does include one or more time-shifted rising or falling edges corresponding to the inserted watermark; and (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
outputting the indication of whether the received radar signal is a skin return signal or an electronic countermeasure signal comprises outputting an indication that the received radar signal is skin return signal. (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58])
Regarding Claim 4, 11, 18, Hodges further teaches:
wherein identifying the first and second subsets comprises randomly or pseudorandomly selecting the first subset of one or more rising or falling edges from among the plurality of rising and falling edges in the initial radar signal to be time-shifted by the one or more predetermined durations. (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58], [col. 8 ln. 63-64] The TM signal can be a random signal that is modulated using transpositional modulation. Hodges does not explicitly teach “first and second subset”.)
Hodges does not explicitly teach the following limitations, however Gulati, in the same field of endeavor, teaches:
first and second subset (Gulati – [0103])
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified the signal modulation of Hodges with the chirp subsets of Gulati in order to determine the random phase difference between the receiving radar and the transmitting (interfering) radar (Gulati – [0103]).
Regarding Claim 5, 12, 19, Hodges further teaches:
wherein the first subset comprises a plurality of respective rising or falling edges from among the plurality of rising and falling edges. (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 54-58], [col. 8 ln. 30-47] a TM capable radar systems can configure attributes of a TM signal to generate TM signals that lie outside of the processing capabilities of enemy ECM devices to reduce the chances of an enemy ECM device inadvertently copying the TM signal… For example, such configurations to TM signals can be used to ensure that at least some of the frequency spectra of the TM signal lies outside of a pass-band of filters used by enemy ECM devices, above a nyquist sampling rate of enemy ECM devices, or both. Hodges does not explicitly teach “first subset”.)
Hodges does not explicitly teach the following limitations, however Gulati, in the same field of endeavor, teaches:
first subset (Gulati – [0103])
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified the signal modulation of Hodges with the chirp subsets of Gulati in order to determine the random phase difference between the receiving radar and the transmitting (interfering) radar (Gulati – [0103]).
Regarding Claim 6, 13, 20, Hodges further teaches:
wherein applying the one or more time shifts of one or more predetermined durations to the first subset comprises (i) applying a first time shift of a first predetermined duration to a first respective rising or falling edge of the first subset and (ii) applying a second time shift of a second predetermined duration different from the first predetermined duration to a second respective rising or falling edge of the first subset. (Hodges – [col. 10 ln. 52-56] Using “internal TM modulation” techniques, for example, TM modulator 304 can generate TM signals which represent covert data by variations the location of time/phase shifts, amplitude shifts, or both time/phase shifts and amplitude shifts of the internal TM signal. Hodges does not explicitly teach “first and second subset”.)
Hodges does not explicitly teach the following limitations, however Gulati, in the same field of endeavor, teaches:
first and second subset (Gulati – [0103])
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified the signal modulation of Hodges with the chirp subsets of Gulati in order to determine the random phase difference between the receiving radar and the transmitting (interfering) radar (Gulati – [0103]).
Regarding Claim 7, 14, Hodges further teaches:
wherein each of the one or more predetermined durations of the one or more time shifts is less than a duration of the inverse of an expected Nyquist frequency of an electronic countermeasure system. (Hodges – [Abstract], [col. 3 ln. 21-34], [col. 8 ln. 30-47], [col. 8 ln. 54-58])
Response to Arguments
Applicant’s arguments, see Pages 9-11, filed 02/03/2026, with respect to the rejection under 35 U.S.C. § 102(a)(1) have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument. The claims are now rejected under 35 U.S.C. § 103 where the combination of Hodges and Gulati have been cited to teach the amended claims.
Applicant’s arguments, see Page 10, filed 02/03/2026, with respect to the rejection under 35 U.S.C. § 102(a)(1) have been fully considered and are not persuasive. Applicant argues that the dependent claims are allowable due to the dependency on the independent claims. The examiner disagrees due to the above-mentioned rejections.
Applicant's remaining arguments amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims is understandable and distinguishable from other inventions.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
The prior art made of record and not relied upon is considered pertinent to applicant's
disclosure or directed to the state of art is listed on the enclosed PTO-892 mailed on 03 November 2025.
The following is a brief description for relevant prior art that was cited but not applied:
Halbert (US 20170285158) describes a radar system that includes electronic countermeasures, using phase/time shifts, Nyquist frequency, and chirp encoding.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BRANDON JAMES HENSON whose telephone number is (703)756-1841. The examiner can normally be reached Monday-Friday 9:00 am - 5:00 pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Resha H. Desai can be reached at (571) 270-7792. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/BRANDON JAMES HENSON/Examiner, Art Unit 3648
/RESHA DESAI/Supervisory Patent Examiner, Art Unit 3648